Sunday, December 11, 2016

Setting the Target PositionWhen I tried that, I got an error message "Value Entered Out of Range. Must be between 0 and 0".Upon checking the "Setup" tab, I noticed that both the "Min Value" and "Max Value" were set to 0. When I tried to set the "Max Value" to a larger number, it seemed to do something (app was blocked for a second or two). But when control returned, it was still set to 0. Tried many things, always with the same result.It then wasn't surprising that I couldn't set the "Min Value" - it always gave an error: "Min Position must be less than Max Value".I also checked the Diagnostics tab, but it showed 0 corrupted packets and 0 packets dropped.

Updating FirmwareNext thing I tried was to update the Firmware of the controller. Mine was at 3.8, the last version was 4.4. I used the MicroTouch Flash Loader appI selected the MicroTouch_4_4.bin file. But when I press "Program", the Status changed from "Idle" to "Opening USB Port" ... and then nothing happened. Always the same result

But I could change the focuser position with the IN and OUT button on the handcontroller, so I thought that I should be able to change it with the up and down arrows in the Controller app. But nothing happened when I pressed those.... until I plugged in a mouse (instead of using the Asus touchpad)! Then the buttons suddenly worked!!! I have absolutely no idea what this is about. The touchpad click should trigger the exact same even then a mouse press...Well at least I know now how I could use it.

From SGProIn SGPro, I selected "MicroTouch Focuser 1" as my focuser (the app / handset is able to control 4 focusers in parallel). Then I clicked setup ... nothing changed. Until I noticed that SGPro opened a new window UNDER its own window (I think I noticed that with other popups before). This was the "MicroTouch Focuser Setup" popup:I opened the drop down menu of "Focuser 1" and selected the entry 1532 - I guess that's the serial number of my focuser ...Then everything worked in SGPro! Could move focuser in and out and also set absolute positions!!! (unlike in the MicroTouch Controller app)

From TheSkyXThere were some instructions in the MicroTouch drive/app package to copy certain files into the TSX directories. But when I tried that, the same files were already there. Seems as if TSX is packaging these up right now. But when I then tried to connect to the focuser I always received an error "No connection to the device. Error = 215."And when I then read the instructions again, they said that I would need firmware version 4.4 in my controller to connect to it. So, back to #2.

I sent an email to Starlightinstruments and asked for help with #1 and #2...

3. Take the little screw out and remove the piston. I found that it was easiest by putting the pressure tuner on a paper towel as the piston inside was very greasy:

4. Now insert the new piston

5. And now insert the new screw (with a hole in it) and tighten the piston

6. Finally put the new cover cap (also with a hole) on it:

and put the pressure tuner on the scope again (tighten it all the way)

Now, we connect the pressure tuner with the air pipe to the PC-USB unit

Powering on the PC-USB unit shows:

And once done, we can set a target pressure and the unit will adjust accordingly (you can hear the pump in the unit working!) It usually sets the pressure slightly higher and once the pressure drops, it will increase it again to stay around the target value.

Of course, I wanted to focus my new Lunt scope also from the computer. Luckily, I still had a Micro Touch Focusing System that I once tried to use on my Edge scope. I checked with Wayne from Starlight Instruments and it turned out that I could even use the MSM20 stepping moter from the EDGE scope.

... but when I tried it, the motor didn't work well - got stuck from time to time, so I had to order a new one.

Installation of the motor on the Feathertouch Focuser is fairly simple. The motor gets attached on the side of the red micro focusing cog:

1. we unscrew the red cog:

2. we unscrew the black wheel:

3. Take the little cog that came with the MSM20 motor

push it flush on the axis and tighten the screw

Finally, take the motor

Push it onto the axis. Might have to wiggle it a little to make sure that the two cogs interlock

until it is completely on the axis and you can't see any silver anymore

and finally tighten the screw:

And now we connect the motor to the Micro Touch Focusing unit and can either more the focuser in out with the control box

Wednesday, November 23, 2016

When I tried to upload the jpg from my latest mosaic to Blogger I always got an error message (image too large). I reduced the images size more and more until it was a few K (and a horrible resolution). But still the same error.

And then it dawned on me: maybe it's not the image size, but the image dimensions! I reduce the image dimensions by 50%, created a JPG (5.2M) ... and could upload it with no issues!!!

A more specific error message in Blogger ("image too large") would have been helpful here ...

In the past I tried a couple of times to save an image in Pixinsight and process it in Photoshop. I figured that the best format would be TIFF. But every time I tried it, the image opened up in black and white or with very distorted color.
Turns out I have to chose "16-bit unsigned integer"!

And upon closer inspection of my two Ha images, it turns out that one has a dimension of 9561x11410 and the other of 9561x11409 (i.e. one row less then the first one). I read about it and it turns out that this can happen when StarAlignment tries to align my images with the rough mosaic and through corrections, the resulting image "sticks" a little out. When looking at my rough mosaic:

You can see that the image on the lower bound and lower left and upper right comes right to the end. I.e. it's easy that individual pixels can be moved over resulting in two images that don't have the same dimensions.
Some people recommend to fixing it by just use the Resample process to adjust the dimensions of one image to the other. I didn't like the idea to needlessly shift the image by a column/row and loose some accuracy in the data.
After trying various ideas, I realized that I can fix this by just making the rough mosaic image a little larger:

Extended image (using DynamicCrop)

This is easy using the DynamicCrop process and dragging the borders outwards.

Now, when aligning the rough mosaic with the individual images, the dimensions are the same - plus some black borders around the image:

But the dimensions are the same! And now I can use GradientMosaicMerge to merge them together to one larger image:

Thursday, November 3, 2016

I wanted to use DrizzleIntegration in Pixinsight. I read a lot about it and how it improves the stacked images.

I processed my latest images of the Bubble Nebula and surrounding as I always do plus created Drizzle files. The ImageIntegrated image looks good. But the DrizzleIntegrated image shows some hot pixels:

I tried a number of things:

lower the "Linear Fit High" value

play with the "Drop Shrink" value in DrizzleIntegration

<several other things that I can't remember>

always with the same outcome: left over hot pixels!

I left a message on the Pixinsight Forum asking for help. And received A LOT of feedback and help from Vicent Peris - he seemed to know a lot about this. We tried a lot of things (and I learnt A LOT) but always with the same outcome. Vicent finally tried my data and for him it worked!!! The main difference was that he used an older version of the ImageIntegration process. Apparently the latest version had a problem with rotated images (and some of my frames did of course rotate during registration).

...

Yesterday the new ImageIntegration process came out ... and it is fixed!!! No more hot pixels!!! So, now I can actually go back to processing my Bubble Nebula images.

Tuesday, October 25, 2016

I wanted to try out using the subframeselector script to assign weights to all frames. For that, I needed the gain of my camera. I can't find the data sheet from FLI anymore, but Richard told me a quick way to estimate the gain good enough:

Take two flats.

Raise the level of one of the flats slightly.I am doing that in Pixinsight by using the Pixelmath expression $T[0]+0.2.

Subtract the other flat from this first flatAgain, in Pixelmath: Ha_01270-Ha_01269. (these are the names of the flat fit files).

Measure the standard deviation in the middle.In Pixinsight, I create a preview in the middle of the new image and with the Statistics process measure 5.1259e-003 = 328.06 DNA (*64000)

Divide by sqrt(2) = 231.97 - this is the noise (or to be exact the quadrature sum of shot noise and read noise)

Now subtract a bias frame from one of the two flats

Use the same region (I drag and drop the preview that I created in step #4) and measure the average value: 6.1413e-001 = 39304.32 DNA (this is the signal)

My first approach was to use the measured differences to correct each light frame that I took. But that would have meant to do this over and over again every time I have new data...

Instead I decided to adjust my dark frame (subtract the difference in the respective columns). Then I would have to do it only once. Of course, I would only correct the dark frames that are used for lights. The much shorter dark frames that I use for calibrating flat frames I would leave as-is.

Using Pixelmath in Pixinsight, I could easily correct each column:

Doing this for both columns resulted in this dark frame:

Compare this to the original dark frame:

One can see that the columns are still there, but much more subdued.

With this dark, I calibrated and stacked my Ha frames again:

No dark columns - compare with the original stack:

I also checked other filters and they got corrected well too. So, from now on I'll use the corrected dark frames for calibrating and everything is fine!!!